The everyday buildup of ice upon the surfaces of mechanical, physical, and natural objects is a familiar annoyance, and quite often a safety hazard. The slick layers of ice that form on highways, driveways, and walkways make transportation difficult. The masses of ice that accumulate within or upon industrial, agricultural, or other mechanical equipment make operation of the equipment difficult or impossible; and the weight of ice that weighs upon power lines, buildings, and signs often causes damage to those structures.
Ice accumulation upon vehicles, such as air or marine vehicles, poses a challenging problem. For example, ships traveling in the arctic and other cold climates may have ice form thereon, thereby disadvantageously increasing the weight and decreasing the maneuverability of the ships.
Similarly, buildup of ice upon the wings and components of an aircraft is of particular concern. The lift generated by the wings, and thus the ability of the aircraft to become and remain airborne, is dependent on the shape of the wings. Even a small accumulation of ice upon the surface of the wings can significantly increase drag and dramatically reduce lift. Further, ice buildup along control surfaces of the aircraft can impede the movement of those surfaces and prevent proper control of the aircraft.
Ice formation and accumulation on transparencies such as windows of air, marine and land vehicles is particularly troublesome. It is well known that ice formation and adhesion to vehicular windows can make safe operation dreadfully difficult. Many approaches have been attempted to provide a means of controlling ice formation and accumulation on transparencies. For instance, the use of per-fluoroalkyl silanes has been employed. However, compositions of this type lose their water-repellant nature quickly and need to be regenerated frequently. The use of quaternary ammonium siloxane-based materials have been incorporated into windshield washing fluids, but this approach fails to provide an anti-icing coating and readily washes away during use. Others have attempted to utilize silicone rubber. However, the application of silicon rubber requires a chemical vapor deposition process and once in use it undergoes rapid wear and picks up oils and dirt.
Additional approaches to mitigate the problem of ice formation and accumulation on transparencies include the use of metal alkoxides (e.g. silicon alkoxides) and using a sol-gel process to form a metal oxide layer on a glass substrate followed by using another sol-gel process to form a water-repellent layer on top of the metal oxide layer. The process, however, requires a high temperature to effect the required coating; hence, it is not suitable for rapid application to glass by merely spraying the coating onto the glass. Others techniques include using a sol-gel based spray coating with a silica underlayer and a fluorocarbon overlayer to obtain water-repellency for use in automobile glass. It has been found, however, that the water-repellency degrades from sunlight, water and abrasion.
Although numerous approaches have been explored for easily imparting a durable and long lasting surface coating to various substrates including transparencies, these past attempts have failed.
What is needed is a durable surface coating with long lasting anti-icing and/or de-icing properties which can be applied to a variety of substrates including transparencies. What is further needed is a surface coating that may be easily applied to the surface, especially to transparencies of a vehicle such as an aircraft, and which retains its functionality under a variety of environmental conditions, such as those typically encountered by a commercial or military vehicle. What is further needed is a method of applying the surface coating to at least a portion of a vehicle.